Methods and devices for mitral valve chordae repair

Abstract

A transvascular artificial chord implantation method and device are disclosed. A catheter is advanced into the left atrium. The catheter can be anchored to the upper surface of the mitral valve leaflet from the atrial side, and a leaflet anchor can be advanced into the mitral valve leaflet to fix the mitral valve leaflet to the leaflet suture. The ventricular anchor is anchored to the ventricular wall to fix the ventricular wall to the ventricular suture. The leaflet suture and the ventricular suture can be tensioned and connected by a suture lock to form an artificial chord.

Description

[0001] Incorporation by reference of any priority application

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 641,612, filed on March 12, 2018, under 35 U.S.C. §119(e), the entire contents of which are incorporated herein by reference for all purposes. This application is also a continuation-in-part of U.S. Application No. 15 / 858,671, filed on December 29, 2017, which is a continuation-in-part of U.S. Application No. 15 / 638,176, filed on June 29, 2017 (now U.S. Patent No. 9,877,833), which claims priority to U.S. Provisional Application No. 62 / 441,031, filed on December 30, 2016, the entire contents of each of which are incorporated herein by reference for all purposes. Any and all applications with foreign or domestic priority claims identified in the Application Data Sheet filed with this application are incorporated herein by reference pursuant to 37 CFR 1.57. Technical Field

[0003] The present disclosure relates to mitral valve repair or replacement, and more generally to methods and devices for mitral valve remodeling, repair and / or replacement of mitral valve chordae tendineae to restore normal function of the mitral valve from mitral regurgitation conditions. Background Art

[0004] The heart includes four heart valves that allow blood to pass through the four chambers of the heart in one direction. The four valves are the tricuspid valve, the mitral valve, the pulmonary valve, and the aortic valve. The four chambers are the right and left atria (upper chambers) and the right and left ventricles (lower chambers).

[0005] The mitral valve is formed by two leaflets, called the anterior and posterior leaflets, which open and close in response to pressure exerted on the leaflets by the pumping of the heart. Several problems may develop or occur with the mitral valve. These problems include mitral regurgitation (MR), in which the mitral valve leaflets do not close properly, which may result in leakage of the mitral valve. Severe mitral regurgitation may adversely affect heart function and impair the patient's quality of life and lifespan.

[0006] Several techniques have been developed for correcting mitral regurgitation. Depending on the stage and underlying cause, these techniques include heart transplantation, valve replacement or repair, chord shortening or replacement, and mitral ring repair also known as annuloplasty.

[0007] Because correction involves chordal replacement or repair, certain surgical and transapical approaches have been proposed. Despite these efforts, there remains a need for a transvascular approach for chordal replacement or repair that reduces or eliminates MR. Summary of the invention

[0008] One aspect of the present invention includes a method for transvascular implantation of artificial chordae, the method comprising the steps of: advancing a catheter into the left atrium, through the mitral valve, and into the left ventricle; deploying a ventricular anchor from the catheter and into the wall of the left ventricle, leaving a ventricular suture attached to the ventricular anchor and extending proximally through the catheter; advancing a leaflet anchor through the upper surface of the mitral valve leaflet from the atrial side to position the leaflet anchor against the lower (ventricular) side of the leaflet using a leaflet suture extending proximally through the leaflet, into and through the catheter; and securing the leaflet suture to the ventricular suture at the top of the leaflet coaptation edge to limit the range of travel of the leaflet in the direction of the left atrium.

[0009] Another aspect of the present disclosure is a leaflet anchor deployment system comprising: a catheter having a proximal end and a distal end; a leaflet anchor positioned on the distal end of the catheter; and a needle capable of being advanced through the leaflet anchor, the needle being capable of releasably carrying a radially expandable leaflet anchor preloaded therein and having a suture extending proximally through the catheter.

[0010] According to another aspect of the present invention, a method for implanting artificial tendons through a blood vessel is provided. The method includes the following steps: advancing a catheter into the left atrium, through the mitral valve, and into the left ventricle; deploying a ventricular anchor from the catheter and entering the wall of the left ventricle, leaving the ventricular suture attached to the ventricular anchor and extending proximally through the catheter; fixing the leaflet anchor catheter to the mitral valve leaflet from the atrial side; with the leaflet anchor catheter fixed to the leaflet, advancing the leaflet anchor from the catheter through the mitral valve leaflet to fix the mitral valve leaflet to the leaflet suture, wherein the leaflet suture extends proximally through the catheter; and fixing the leaflet suture to the ventricular suture to limit the range of travel of the leaflet in the direction of the left atrium.

[0011] The step of advancing the leaflet anchor from the catheter through the mitral valve leaflet to secure the mitral valve leaflet to the leaflet suture may include: advancing a needle preloaded with the leaflet anchor through the upper surface of the mitral valve leaflet. The step of securing the leaflet anchor catheter to the mitral valve leaflet may include: using a leaflet connector. The leaflet connector may include a helical anchor or a tissue hook.

[0012] According to another aspect of the present invention, a method for fixing a leaflet anchor to a mitral valve leaflet is provided. The method comprises the following steps: advancing a catheter into the left atrium; fixing a leaflet connector coupled to the catheter to the leaflet from the atrial side of the mitral valve leaflet; and after fixing the leaflet connector to the mitral valve leaflet, advancing the leaflet anchor through the mitral valve leaflet to fix the mitral valve leaflet to the leaflet suture.

[0013] The step of advancing the leaflet anchor through the mitral valve leaflet to secure the mitral valve leaflet to the leaflet suture may include advancing a needle preloaded with the leaflet anchor through the mitral valve leaflet from the atrial side. The needle may be advanced through the leaflet connector. The leaflet connector may include a helical anchor.

[0014] According to another aspect of the present invention, a leaflet anchor deployment system is provided. The system includes: a catheter having a proximal end and a distal end; a leaflet connector positioned on the distal end of the catheter; and a needle that can be advanced through the leaflet connector, the needle including a radially expandable leaflet anchor preloaded therein and having a suture extending proximally through the catheter. The leaflet connector can include a helical anchor.

[0015] According to another aspect of the present invention, a new chord deployment system is provided. The system includes: a catheter having a proximal end and a distal end; a helical ventricular anchor subassembly that can extend through the catheter and has a ventricular suture extending proximally through the catheter; and a leaflet anchor deployment subassembly that can extend through the catheter and has a radially expandable leaflet anchor within the subassembly and has a leaflet suture extending proximally through the catheter.

[0016] The radially expandable leaflet anchor may include wadding. The wadding may be transformed from a slender strip configuration to a radially expanded, axially shortened configuration by proximal retraction of the suture. The radially expandable leaflet anchor may include a leaflet suture positioned between two sheets of material. The radially expandable leaflet anchor may be carried in a needle having a tip for piercing the leaflet. The leaflet anchor deployment subassembly may include an elongated tube having a distal end and a central lumen and a leaflet connector on the distal end. The leaflet connector may include a spiral leaflet anchor. The needle may be axially movable relative to the spiral leaflet anchor. The system may also include: a suture locking subassembly that may be advanced through a catheter and is configured to connect the ventricular suture to the leaflet suture.

[0017] According to another aspect of the present invention, a leaflet anchor delivery subsystem is provided. The subsystem includes: an elongated flexible tubular body having a proximal end, a distal end, and a central lumen; a deployment needle that can be axially advanced through the central lumen; a leaflet anchor carried within the deployment needle; and a leaflet connector carried by the distal end of the tubular body. The leaflet anchor may include a helical element. The deployment needle can extend axially through the helical element.

[0018] According to another aspect of the present invention, a tissue anchor is provided, which includes a hub, a suture extending proximally from the hub, a helical anchor extending distally from the hub, and a core wire extending concentrically through the helical anchor and beyond the distal end of the helical anchor.

[0019] The tissue anchor may also include a suture anchor guide extending proximally from the hub. The tissue anchor may also include a tubular sleeve extending proximally from the hub and having a length not exceeding about 10 cm. The tissue anchor may also include a radiopaque marker carried by the sleeve. The tissue anchor may also include a radiopaque marker carried axially movably by the core wire. The tissue anchor may also include a spring carried by the core wire. The tissue anchor may also include: a tissue piercing point at the distal end of the spiral anchor; and a barb on the spiral anchor, the barb being configured to resist rotation of the spiral anchor in engagement with the tissue.

[0020] According to another aspect of the present invention, a tissue anchor with a dynamic depth indicator is provided. The tissue anchor comprises: a hub; a tissue anchor extending distally from the hub; a core wire extending distally from the hub; a radiopaque marker movably carried by the hub; and a spring for biasing the radiopaque marker in a distal direction; wherein the radiopaque marker is advanced proximally relative to the tissue anchor in response to advancement of the tissue anchor into tissue.

[0021] According to another aspect of the present invention, an intravascular suture lock is provided. The suture lock includes: a body having a suture path extending therethrough; a movable wall in the housing for reducing the cross-sectional size of the suture path; a rotatable coupling on the housing; and a drive mechanism for advancing the movable wall in response to rotation of the coupling.

[0022] The suture lock may further include a friction enhancing surface exposed to the suture path. The friction enhancing surface may be located on the movable wall. The suture lock may include a push wedge having an angled surface and being axially movable within the housing. Rotation of the coupler may axially advance the push wedge, which will laterally advance the movable wall to change the cross-sectional size of the suture path. The movable wall may include a suture clamping surface on a first side and a ramp surface on a second side, the ramp surface being configured for sliding contact with the angled surface on the push wedge. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.It should be understood that these drawings depict only several embodiments in accordance with the present disclosure and should not be considered limiting of the scope.

[0024] Figure 1 Placement of a ventricular anchor to the mitral valve via a transseptal approach is illustrated.

[0025] Figure 2A and Figure 2B A ventricular anchor is illustrated.

[0026] Figure 2C is a perspective view of a ventricular anchor on the distal end of a ventricular anchor deployment tool.

[0027] Figure 2D is a stereoscopic view of the proximal end of a ventricular anchor deployment tool.

[0028] Figure 2E is a partially exploded perspective view of a ventricular anchor and a distal end of a ventricular anchor deployment tool.

[0029] Figure 3 The deployment end of the catheter is illustrated positioned to engage the leaflets of the mitral valve.

[0030] Figure 4 The leaflet is illustrated captured by the helical leaflet anchor and a needle is passed through the leaflet from the atrium to the ventricle.

[0031] Figure 5 A quilted leaflet anchor is illustrated being deployed from a needle and into a ventricle.

[0032] Fig. 6A Proximal traction on the leaflet sutures is illustrated to collapse the padding against the ventricular side of the leaflet.

[0033] FIG. 6B to FIG. 6D Details of a quilted leaflet anchor are illustrated.

[0034] Figure 7Illustrated are a deployed ventricular anchor and suture as well as a deployed leaflet anchor and suture ready for tensioning and attachment of a suture lock.

[0035] Figure 8 A perspective view of the distal end of a leaflet anchor delivery subsystem is illustrated.

[0036] Fig. 9 A perspective view of the proximal end of a leaflet anchor delivery subsystem is illustrated.

[0037] Fig.10 An exploded view of the distal end of the leaflet anchor delivery subsystem is illustrated.

[0038] Fig.11 Depicted is advancing a suture lock via a suture lock delivery subsystem over the leaflet anchor suture and the ventricular anchor suture to connect the leaflet anchor to the ventricular anchor.

[0039] Fig.12 The suture lock is depicted in a locked position after the tension has been adjusted and the suture tail has been cut.

[0040] Fig.13 A perspective view of the distal end of the suture lock delivery subsystem is depicted.

[0041] Fig.14 A perspective view of the proximal end of the suture lock delivery subsystem is depicted.

[0042] Fig.15 A partially exploded view of the distal end of the suture lock delivery subsystem is depicted.

[0043] Fig.16 A perspective view of the distal end of a suture cutting assembly is depicted.

[0044] Fig.17 Depicted is a side view of a cutting assembly portion of a suture lock delivery subsystem in a configuration where the cutting head has not been advanced for holding the suture prior to severing the suture.

[0045] Fig.18 Depicted is a side view of a cutting assembly portion of a suture lock delivery subsystem in a configuration in which the cutting head has been advanced for severing sutures.

[0046] Fig.19 Depicted is a side view of a suture lock and a distal end of a torque driver configured to engage the suture lock.

[0047] Fig. 20 A proximal view of the suture lock is depicted.

[0048] Fig.21 A distal view of the suture lock is depicted. DETAILED DESCRIPTION

[0049] U.S. Patent Application 15 / 858,671, filed December 29, 2017, the entire contents of which are incorporated herein by reference, discloses systems and methods for transvascular artificial chord implantation. One aspect involves: advancing a catheter into the left atrium, through the mitral valve, and into the left ventricle; deploying a ventricular anchor from the catheter and into the wall of the left ventricle, leaving a ventricular suture attached to the ventricular anchor and extending proximally through the catheter; and advancing a leaflet anchor into the mitral valve leaflet to secure the mitral valve leaflet to the leaflet suture, wherein the leaflet suture extends proximally through the catheter, and the leaflet suture extends over the top of the coaptation edge and secures the leaflet suture to the ventricular suture to limit the range of travel of the leaflet in the direction of the left atrium. Certain aspects are further developed herein.

[0050] Access to the mitral valve can be achieved through a standard transseptal approach to provide access to the left atrium. For this access, a first step can include securing a leaflet capture catheter to the leaflets of the mitral valve in a position determined to best correct regurgitation. Probing the leaflet surface from the superior atrial surface can advantageously provide immediate feedback regarding the optimal location for adding additional mitral chordae tendineae. In another embodiment of the invention, the ventricular anchor is deployed first, followed by the leaflet anchor.

[0051] See also Figure 1 , a ventricular anchor such as a spiral anchor 32 has been deployed near the apex 20 of the left ventricle 24. Although the spiral anchor 32 is shown in the following figures as being positioned near the apex 20, the anchor 32 can be attached at a point of thin tissue that deviates from the apex, and can be implanted in the usually thicker adjacent wall of the ventricle, such as between two papillary muscles. This allows the implanted new chord structure (suture, optional new papillary muscle and / or spiral anchor) to be aligned along a longitudinal axis that is substantially parallel to the original path of the native chord or coaxial with it. In some embodiments, the implanted new chord structure is aligned along a longitudinal axis that is within 5 degrees, 10 degrees or 15 degrees parallel to the original path of the native chord and / or the path of the adjacent native chord. In addition, although a spiral anchor is illustrated, the anchor can have a different structure for engaging cardiac tissue, whereby other tissue anchor structures can be used to replace the spiral structure including various piercing, hooks or radially expandable structures known for engaging tissue.

[0052] See also Figure 2A and Figure 2B, illustrates one embodiment of a tissue anchor suitable for use as a ventricular anchor according to the present invention. Anchor assembly 50 will be described primarily in the context of chordal repair applications of the present invention, however, the anchor may be used in any of a variety of other applications where a soft tissue or bone anchor may be desired.

[0053] The anchor assembly 50 generally includes a coil 54, which can include any of a variety of materials, such as stainless steel or nitinol. The coil 54 extends helically between a proximal end 56 and a distal end 58. The distal end 58 is provided with a sharp tip 59 and also carries a retaining barb 61, which is configured to resist reverse rotation of the coil and disengagement from the tissue. The proximal end 56 of the coil 54 is carried by a hub 57 (attached to it or formed integrally with it) discussed in further detail below.

[0054] Extending distally from the hub 57 and within the coil 54 is an elongated core wire 62 having a sharp tissue-piercing distal end 64. The distal end 64 is positioned distal to the distal end 58 of the coil 54. This enables the sharp distal end 64 to pierce the tissue upon contact and before the coil 54 begins to rotate to embed the coil 54 within the target tissue. Engaging the distal end 64 prior to rotating the anchor stabilizes the anchor to prevent lateral movement, thereby allowing a single placement of the anchor assembly 50 against the tissue and rotation of the coil 54 to engage the tissue without the anchor "leaving" the desired target site, as will be understood by those skilled in the art. The proximal end of the core wire 62 can be attached to the hub in any of a variety of ways, such as by soldering, brazing, adhesives, and / or mechanical interference, such as by entering an orifice in the sidewall or other surface of the hub 57.

[0055] A radiopaque depth marker 66 is provided with an aperture 68 and is axially movably carried on the core wire 62. A distal stop 70, such as a radially outwardly extending protrusion or annular ridge, is carried by the core wire 62 and spaced proximally of the sharpened distal end 64 to provide a core wire guide segment 72 on the distal side of the stop 70 so that the marker 66 cannot interfere with the tissue anchoring function of the distal tip 64. The stop 70 is used to limit the distal travel of the marker 66. The marker 66 can be an annular structure, such as a disk with a central aperture for receiving the core wire 62.

[0056] The coil spring 71 is concentrically carried on the core wire 62 and biases the radiopaque marker 66 in the distal direction. Thus, the radiopaque marker 66 is held in place against the proximal surface of the stop 70. In use, the marker 66 rests on the tissue surface at the target attachment site. As the helical coil anchor 54 rotates and advances distally into the tissue, the marker 66 rests proximally on the core wire 62 together with the tissue surface to compress the coil spring 71 until the marker 66 retracts proximally to the hub when the tissue anchor is fully embedded. This enables the process of the coil into the tissue and the endpoint of the complete engagement of the coil 54 embedded in the target tissue to be visualized fluoroscopically by observing the changing distance between the marker 66 and a reference such as the hub 57 or other radiopaque markers.

[0057] The hub 57 includes a proximal connector for engaging with a rotary driver as described elsewhere herein. In one embodiment, the connector includes an aperture, such as a hexagonal aperture, for removably engaging a complementary surface structure on the distal end of the driver. Suture 74 is fixed to the anchor assembly 50, such as to the hub 57, the coil 54, or the core wire 62. In the illustrated embodiment, the suture 74 is attached to a cross pin 76, which can be inserted through one or two apertures in the side wall of the hub and through the central hub lumen. The suture can additionally carry one or two or more radiopaque markers 82 spaced from the hub 57 and can extend proximally through the proximal connector and the central lumen in the rotary driver.

[0058] A suture lock guide, such as a tubular sleeve 78, extends proximally from the hub 57 by at least about 2 mm, or 4 mm, or 8 mm, but typically no more than about 5 cm or 2 cm, depending on the desired performance. The guide sleeve 78 may include a flexible material, such as ePTFE. Preferably, a radiopaque marker band 80 is carried by the proximal end of the sleeve 78 and is axially spaced from the marker 82 on the suture 74 to facilitate fluoroscopic visualization of the suture lock as it is advanced distally over the suture 74. The marker band 80 may be positioned between the inner and outer layers of the ePTFE sleeve, such as may be created by placing the band on the sleeve and flipping the sleeve over on itself to capture the loop.

[0059] The suture lock guide may include any of a variety of structures, such as a sleeve or an alignment pin as illustrated, which extends proximally from the hub and is received within a lumen in the suture lock for maintaining the orientation of the suture lock after separation from the deployment catheter. Since the tension on the suture is optimized while the suture lock is held in place by the deployment catheter, any change in the orientation of the suture lock after release from the catheter will affect the tension on the leaflets and potentially negatively affect the therapeutic value of the implant. The suture lock guide helps to maintain a constant maximum distance between the ventricular anchor and the leaflet anchor both before and after deployment from the catheter. In this way, the maximum tension on the leaflet suture (during systole) remains unchanged before and after catheter separation, after the suture lock has been locked.

[0060] The helical anchor assembly 50 may be delivered by the ventricular anchor delivery subsystem 300 . FIG. 2C to FIG. 2E Various views of the ventricular anchor delivery subsystem 300 and its components are illustrated. Figure 2C A perspective view of the distal end of subsystem 300 is depicted. Figure 2D A perspective view of the proximal end of subsystem 300 is depicted. Figure 2E A partially exploded view of the distal end of subsystem 300 is depicted.

[0061] The subsystem 300 can be delivered by a delivery catheter 100. The delivery catheter 100 can be accessed into the left atrium by conventional techniques (such as by atrial transseptal puncture). As the various subsystems are placed in and removed from the delivery catheter 100, the delivery catheter 100 can remain in a substantially constant position throughout the process. For example, the distal end of the delivery catheter 100 can be positioned in the left atrium. In other embodiments, the distal end of the delivery catheter 100 can be positioned in the left ventricle for the entire duration of the process.

[0062] like FIG. 2C to FIG. 2E As shown, the ventricular anchor delivery subsystem 300 can include an outer sheath 304, a drive shaft 307 and a drive head 306, an anchor hub 308, and an anchor 302. The anchor can be a helical anchor 302, and the drive head 306 can be configured to rotate the helical anchor 302. The helical anchor 302 can include an inner diameter that is configured to be received on an outer diameter of the anchor hub 308. The helical anchor 302 can be securely secured to the anchor hub 308 by an interference fit or other frictional engagement, brazing, or other known attachment techniques. The anchor hub 308 can be implanted with the helical anchor 302.

[0063] The anchor hub 308 may include a lumen positioned substantially along the central axis of the anchor hub 308 for receiving the suture 74 ( Figure 2A) and attach the suture 74 to the helical anchor 302. In some embodiments, the suture 74 can include an attachment element (e.g., a knot or washer) having a diameter sized to prevent the suture 74 from being pulled proximally through the lumen of the anchor hub 308. For example, the suture 74 can be tied on the distal side of the lumen. In some embodiments, the suture 74 can be tied to the anchor hub 308 (e.g., through the lumen, wrapped around a structure such as an outer surface or a cross pin 76, such as Figure 2B as shown, and tied to itself).

[0064] The helical anchor 302 may include a distal segment of the winding and a proximal segment of the winding. The proximal segments of the winding may be spaced closer together than the distal segments of the winding and may be configured to secure the helical anchor 302 to the anchor hub 308. The distal segments of the winding may be spaced farther apart than the proximal segments of the winding and may be configured to be inserted into ventricular tissue. The anchor hub 308 may include an enlarged cross-section at its proximal end that is configured to abut the helical anchor 302 and / or prevent the helical anchor 302 from advancing proximally on the proximal end of the anchor hub 308. Other helical anchors, such as those described elsewhere herein, may also be configured for use with the ventricular anchor delivery subsystem 300 described herein.

[0065] The proximal face of the helical anchor 302 can include a recess for receiving an extension 306' of the driver head 306. The recess can be non-circular (e.g., rectangular or polygonal, such as a hexagon) so that it is configured to transfer torque from the driver to the anchor hub 308 when the driver is rotated. The recess can be positioned around the central lumen of the anchor hub 308.

[0066] In other embodiments, the anchor hub 308 may include an extension and the driver 309 may have a complementary recess. The drive head 306 may be generally cylindrical with a distally facing post or orifice having a complementary configuration for rotationally engaging a corresponding component on the anchor. The drive head 306 may be fixedly coupled to a drive shaft 307. The driver may include a central lumen passing through the drive head 306 and a drive shaft 307 configured to receive the suture 74. The central lumen of the driver may be configured to align with the central lumen of the anchor hub 308. The drive shaft 307 may be received within the guide shaft 305. The diameter of the drive head 306 may be greater than the inner diameter of the guide shaft 305. The size of the outer sheath 304 may be designed to receive the guide shaft 305 as well as the drive head 306, the anchor hub 308, and the spiral anchor 302.

[0067] The outer sheath 304 can be delivered into the left ventricle via the delivery catheter 100 and proximal to the ventricular attachment site. In some embodiments, the outer sheath 304 can be delivered without a delivery catheter. In some embodiments, the spiral anchor 302 can be hidden in the outer sheath 304 until the outer sheath 304 is positioned proximal to the ventricular attachment site, and then pushed through the outer sheath 304 toward the distal side, or the outer sheath 304 is retracted toward the proximal side so that the spiral anchor 302 is exposed. The spiral anchor 302 can be placed in contact with the ventricular tissue. The rotation of the drive shaft 307 can rotate the drive head 306, the anchor hub 308 and the spiral anchor 302, thereby screwing the spiral anchor 302 into the ventricular tissue. The rotation of the driver 309 can axially advance the driver 309, the anchor hub 308 and the spiral anchor 302 in the distal direction relative to the outer sheath 304.

[0068] like Figure 2D As shown, the user can manually rotate the drive shaft 307 using the drive handle 312. The proximal end of the ventricular anchor delivery subsystem 300, such as Figure 2D As an example, a first hemostasis valve 314 and a second hemostasis valve 316 may be included. The first hemostasis valve 314 may be positioned distal to the drive handle 312 and may provide access to the guide shaft 305. The second hemostasis valve 316 may be positioned proximal to the drive handle 312 and may provide access to the central lumen of the driver. A ventricular anchor suture (not shown) may extend through the second hemostasis valve 316.

[0069] In some embodiments, the insertion portion 306' of the driver head 306 and the recess of the anchor hub 308 can have a frictional engagement that temporarily holds the two components together. Once the spiral anchor 302 is inserted, the frictional engagement can be overcome when the driver is retracted proximally by the reaction force from the ventricular tissue. In some embodiments, the proximal tension on the suture 74 can provide an engagement force between the proximal hub 308 and the driver head 306, which can be released when the driver 309 is retracted. The driver head 306 can be withdrawn proximally into the outer sheath 304 before the outer sheath 304 is withdrawn into the delivery catheter 100.

[0070] The unimplanted components of the ventricular anchor delivery subsystem 300 can be removed from the delivery catheter 100, and a subsequent subsystem can be placed in the delivery catheter 100 to complete the implantation of the new chordae tendineae. In modified embodiments, the ventricular anchor delivery subsystem 300 and a subsequent subsystem such as the leaflet anchor delivery subsystem 330 can be positioned within the delivery catheter 100 simultaneously, and in certain arrangements, both the tissue and the leaflet anchors can be pre-loaded into the delivery catheter. In alternative embodiments, implantation of the ventricular anchor can be performed in a different order (e.g., after implantation of the leaflet anchor). The ventricular anchor delivery component can be retracted proximally over the proximal end of the suture 74, which can remain extended through the delivery catheter 100 to the ventricular anchor 302.

[0071] Figure 3 Figures 6 through 7 depict the deployment of the leaflet anchor. Figure 3 , the ventricular anchor 32 has been deployed and tethered to the catheter 100 by the ventricular anchor suture 74, and the ventricular anchor subsystem has been removed. The leaflet anchor is carried within a needle 338, which is shown aimed at a target site on the atrial side of the leaflet. The needle 338 is axially reciprocated carried within the catheter 100, such as carried within a tubular sleeve 332 that can be advanced through the catheter 100. Other details of the needle and needle driver are discussed below.

[0072] like Figure 3 As shown, in the illustrated arrangement, the needle can be passed from the atrium through the leaflet to the ventricle, and then the pre-loaded suture can be advanced into the ventricle. Figure 4 As shown, the suture can be used to collapse the wadding against the ventricular side of the leaflet to anchor the suture to the leaflet. Thus, the wadding forms a leaflet anchor that can be expanded radially. In some embodiments, other forms of leaflet anchors that can be expanded radially can be used.

[0073] The leaflet anchors and sutures can then be used in conjunction with the ventricular anchors, sutures, and suture locks to effectively create new mitral valve chordae tendineae, e.g. Figure 5 As described above, the leaflet anchors and sutures can be used in conjunction with the systems and methods for transvascular prosthetic chord implantation disclosed in U.S. Patent Application 15 / 858,671 (the entire contents of which are incorporated herein by reference) and the various embodiments of ventricular anchors, sutures, and suture locks disclosed therein.

[0074] Preferably, the leaflet anchor deployment subassembly is provided with a temporary anchor for capturing and stabilizing the leaflet while the needle tip 338 is advanced through the anchor on the target side. Figure 3 and Figure 4As shown, the distal end 400 of the delivery tube 332 or other system component carries a temporary tissue anchor, such as a helical tissue anchor 402. The anchor 402 can be similar to the ventricular anchor 54, except that the temporary anchor 402 does not have a distal barb because it is intended to engage the leaflet only temporarily. Thus, the anchor 402 includes a helical element 406 that terminates in a distal tip 408.

[0075] In use, the distal tip 408 is positioned at a target site on the surface of the leaflet and the helical element 406 is rotated about its axis to engage and penetrate the leaflet. The needle tip 338 may optionally engage the leaflet before the helical element 406 is rotated and used in a manner similar to that used to engage the ventricular anchor and Figure 2A and Figure 2B The discussed approach stabilizes the anchor to prevent it from leaving the target site in response to rotation.

[0076] After the helical element 406 engages to capture the leaflet from the atrial side and secure the leaflet to the catheter, the needle can be advanced distally through the central lumen defined by the helical element 406 and completely through the leaflet so that the needle tip 338 exits the ventricular side of the leaflet, as shown. Figure 4 An anchor deployment actuator, such as a pusher extending through the needle, may be used to deploy the anchor from the needle and into the ventricle.

[0077] See also Figure 5 , the leaflet anchor can be a wadding 340 similar to the wadding described elsewhere herein. The wadding 340 can be coupled or attached to the distal end of the leaflet anchor suture 344. The wadding can include a soft and / or flexible material, such as fabric. The suture 344 can extend through the needle 336. The wadding 340 can be folded or compressed in a configuration including a reduced radial cross-section so that it can be arranged within the needle 336 for delivery, as discussed below. Figure 8 and Fig.10 When deployed from the distal end of the needle tip 338, the filler 340 can expand from a reduced cross-section to present a larger radial cross-section, such as Figure 5 In some embodiments, the wadding 340 can be pushed through the needle 336 via a push line or release line (not shown). After delivery through the needle tip 338, proximal retraction of the leaflet suture 344 as shown in FIG. 6 can cause the leaflet anchor to assume an axially collapsed, radially expanded configuration that prevents the leaflet anchor from retracting through the perforation in the leaflet, thereby anchoring the leaflet suture 344 to the leaflet, as shown in FIG. Figure 7 shown.

[0078] FIG. 6A to FIG. 6DThe padding 340 is schematically depicted connected to the distal end of the leaflet suture 344. The padding 340 can include two wings 341, 342 that can be rolled / folded about the longitudinal axis of the padding 340 (e.g., both in a clockwise or counterclockwise direction) to form a reduced cross-sectional configuration. In some embodiments, the leaflet suture 344 can be formed integrally with the padding 340. To create a foldable or collapsible configuration, the suture 344 can extend distally through the padding, loop around the distal end of the padding, and return proximally and back through one or more orifices (e.g., two orifices, three orifices, four orifices, etc.) formed in the padding 340, such as Fig. 6A In some embodiments, the orifice can be aligned along the center of the wadding 340 .

[0079] The orifice can extend through the wadding 340 and through the portion of the embedded portion of the suture 344 that is integral with the wadding 340. The embedded portion of the suture 344 can be at least partially flattened within the wadding 340. In some embodiments, the orifice can be placed substantially near the center of the wadding (e.g., immediately to the left or right of the embedded suture 344 or alternating between the left and right sides of the suture 344). When deployed, the suture 344 can be effectively coupled to the distal end of the wadding 340 (e.g., the suture 344 can be looped back to the position where it is inserted between the wadding pieces).

[0080] FIG. 6B to FIG. 6D An example of a wadding as described elsewhere herein is schematically depicted. Figure 6B Schematically depicted is a wadding 340 formed by securing the distal end of a suture 344 (shown in phantom) between two flat sheets such that the sheet is for a left wing 341 and a right wing 342 . Figure 6C The filling 340 is shown along Figure 6B Cross section of the BB axis of the example. In some embodiments, the suture 344 can be inserted between the two sheets (e.g., substantially along the middle of the sheet) and extruded and / or laminated to connect the three components together (e.g., under heat and / or pressure). At least one layer can be partially sintered. The suture 344 can be flattened and / or compacted to increase resistance to suture tearing. The sheet can be a flat polytetrafluoroethylene (PTFE) sheet (e.g., a thin uncured expanded PTFE (ePTFE) sheet) or any other suitable material. In some embodiments, the leaflet suture 344 can be arranged between the sheets in an alternative configuration such as a zigzag or s-shaped configuration. Fig.6D Shows Figure 6B The wadding 340 includes a plurality of apertures 343 through which the proximal ends of the sutures 344 may pass.

[0081] In some embodiments, one or more apertures 343 can be formed through the padding in various configurations to form a collapsible structure as described elsewhere herein that is configured to anchor the suture 344 against the mitral valve leaflet. Fig.6D Orifices 343 are shown alternating around opposite sides of a suture 344. In some embodiments, orifices 343 may be formed on the same side of a suture 344 (e.g., in wing 341 or wing 342). In some embodiments, orifices 343 may be formed through suture 344. Orifices 343 may be aligned along the center of the wadding 340. Orifices 343 may be aligned along the length of suture 344 (e.g., may form a straight line). Suture 344 may be at least partially flattened between two opposing sheets, which may facilitate placement of orifices 343 through suture 344. Various combinations of orifices 343 including the above-described positioning may be used.

[0082] The wadding 340 can be formed so that the wings 341, 342 have approximately the same size, or they can be formed to have different sizes. When the leaflet suture 344 is retracted toward the proximal side, the wadding 340 can be folded to present an accordion-like configuration, such as Fig. 6A 340. The wadding 340 can present a configuration including a substantially planar proximal surface that is approximately perpendicular to the longitudinal axis of the leaflet suture 344. This configuration can facilitate anchoring the suture 344 in the leaflet. When the leaflet suture 344 is anchored in the leaflet, the leaflet anchor delivery subsystem 340 can be withdrawn from the delivery catheter 100. The leaflet anchor delivery component can be retracted proximally over the proximal end of the suture 344, which can remain adjacent to the ventricular anchor suture 74 extending through the delivery catheter 100 to the leaflet anchor 340.

[0083] Figures 8 to 10 Various views of the leaflet anchor delivery subsystem 330 and its components are illustrated. Figure 8 A perspective view of the distal end of subsystem 330 is depicted. Fig. 9 A perspective view of the proximal end of subsystem 330 is depicted. Fig.10 An exploded view of the distal end of subsystem 330 is depicted.

[0084] like Figure 8 and Fig.10 As shown, the leaflet anchor delivery subsystem 330 can include an outer delivery tube 332. The tube 332 can optionally include a deflection region and can be configured to be manipulated by an operator, such as by retracting the curved tube 332 proximally along the sides of the curved tube 332 via one or two or more pull wires (not shown). The operator can control the bending of the curved tube via a knob 352 or a lever or other actuation mechanism located on a handle 350 at the proximal end of the leaflet anchor delivery subsystem 330, such as Fig. 9 shown.

[0085] An inner tubular shaft or needle 336 terminating at a distal end with a needle tip 338 can extend through the delivery tube 332. The inner needle 336 can include a hypotube, extruded tube, or braided tube or catheter that is flexible enough to conform to the shape of the optional curved tube 332. The needle tip 338 can be coupled to the distal end of the inner flexible shaft 336. A flexible jacket 333 can surround the curved tube 332 and the delivery shaft 334.

[0086] The proximal end of the inner tubular shaft 336 can be connected to a needle handle 354, such as Fig. 9 As shown. The needle handle 354 may include a hemostatic valve 356. The leaflet suture 344 may be inserted through the valve 356. The valve 356 may be a Tuohy-Borst valve. The needle handle 354 may include an additional port 358 for accessing the lumen of the inner flexible shaft 336. The needle handle 354 may be positioned proximal to the handle 350 so that the inner flexible shaft 336 extends through the handle 350 and into the lumen of the delivery shaft 334. The handle 350 may include a hemostatic valve for receiving the inner flexible shaft 336 and sealing the internal components of the handle including the opening to the delivery shaft 334 from the surrounding environment.

[0087] Needle tip 338 may be capable of being extended and retracted by respectively extending needle handle 354 toward handle 350 or retracting needle handle 354 from handle 350. Distal advancement of needle 336 may be accomplished by manually advancing handle 354. Alternatively, distal advancement of the needle may be assisted by a mechanical or electromechanical mechanism to produce relatively high speed, low stroke length distal advancement.

[0088] Applying pressure on the leaflet as the needle tip 338 extends distally beyond the tube 332 can cause the needle tip 338 to pierce the leaflet, such that the needle tip 338 can extend through to the opposite side of the leaflet (e.g., the atrial side), such as Figure 4 The pressure may be applied by extending the needle tip 338 and / or retracting the entire delivery device 330 in a proximal direction with the needle tip 338 in the extended position.

[0089] The ventricular anchor suture 74 and the leaflet anchor suture 344 can be coupled together in a tensioned manner to form a new chord implant or to join two segments of a new chord implant together so that the new chord extends across the atrial side of the coaptation edge of the leaflet between the ventricular anchor 302 and the leaflet anchor 340. The total length of the new chord can be adjusted by pulling one or both sutures 74, 344 proximally before engaging the suture lock 376 so that appropriate tension is applied to the leaflet, where the tension is then maintained by the ventricular anchor 302. The suture 74, 344 can remain proximally extending through the delivery catheter 100 to a position outside the body. In some embodiments, the proximal end of the suture 74, 344 can be fed into the handle or proximal portion of the suture lock delivery system 370 to facilitate the placement of the suture lock and the cutting of the suture 74, 344. In some embodiments, the proximal end can remain free or be coupled or fixed by other means.

[0090] Fig.11 The advancement of the suture lock 376 over the ventricular anchor suture 74 and the leaflet suture 344 is depicted. The suture lock delivery subsystem 370 can be advanced through the delivery catheter 100, and the tubular pusher catheter 372 can push the suture lock 376 in a distal direction along the sutures 74, 344. Once the suture lock 376 reaches the ventricle, it can continue to be pushed along the ventricular suture 74 using proximal traction on the suture 74, while simultaneously allowing the leaflet suture 344 to be fed distally through the catheter as needed to advance the suture lock 376 distally to the ventricular anchor. As discussed further below, Fig.12 The final configuration is illustrated, in which the leaflet anchor and the ventricular anchor are tied together to form an artificial chord.The proximal tails of both sutures have been cut, and the catheter has been retracted proximally from the ventricle through the mitral valve.

[0091] Figure 13 to Figure 14 Various views of the suture lock delivery subsystem 370 and its components are illustrated. Fig.13 A perspective view of the distal end of subsystem 370 is depicted. Fig.14 A perspective view of the proximal end of subsystem 370 is depicted. Fig.15 A partially exploded view of the distal end of subsystem 370 is depicted. Fig.16 A perspective view of the distal end of the cutting assembly is depicted. Fig.17 and Fig.18 A side view of the cutting assembly portion of subsystem 370 is depicted. Fig.19 A side view of a suture lock 376 and a distal end of a torque driver 388 configured to engage the suture lock 376 is depicted. Fig. 20 and Fig.21 Proximal and distal views of the suture lock 376 are depicted, respectively.

[0092] The suture lock delivery subsystem 370 can be configured to advance (e.g., slide) a suture lock 376 on two sutures 74, 344 (or even three or four or additional sutures) to secure them together. The sutures 74, 344 can each be retracted proximally relative to the suture lock 376 to tension the sutures 74, 344 and adjust the length of each suture 74, 344 between the suture lock 376 and the corresponding tissue anchor 302, 340. Once the tension and length of the new chord implant are optimized, the suture lock 376 can be locked to fix the length of the sutures 74, 344 so that the sutures 74, 344 can no longer move relative to the suture lock 376. Then, the sutures 74, 344 can be cut at a point proximal to the suture lock 376. The sutures 74, 344 can be cut by the same suture lock delivery subsystem 370 that delivers the suture lock 376. In other embodiments, a separate cutting device may be inserted into the delivery catheter 100 after the suture lock is locked in place.

[0093] The suture lock allows one or two or more sutures to be advanced through the suture lock and adjusted, and then locked with sufficient clamping efficiency to prevent the ePTFE suture from sliding from the suture lock under normal use conditions (e.g., withstanding a tension of at least about 60% or 80% or more of the suture breaking strength without sliding). The lock can be reopened to allow readjustment of the tension on the mitral valve leaflets, and re-tightened until the desired result has been achieved. The tightening tool can then be removed, leaving the suture lock behind.

[0094] The suture lock 376 can be advanced along the suture through the retaining catheter 373. The distal end of the retaining catheter 373 can be coupled to a retaining element 377 ( Fig.15 ). The retaining element can include a flange 371 or other mechanical feature configured to engage the suture lock 376. For example, the flange 371 can be inserted into a recess at the proximal end of the suture lock 376. In some embodiments, the retaining catheter 373 can be disengaged from the suture lock 376 using rotation of the retaining catheter 373 and / or translation substantially perpendicular to the axial direction of the retaining catheter 373.

[0095] The sutures 74, 344 may extend from their respective tissue anchors to pass through the suture lock 376 to enter from the distal opening 395 in the distal surface of the suture lock 376 ( Fig.21 ), and exits at the proximal opening 394 to the suture path in the proximal side of the suture lock 376 ( Fig. 20372). The suture 74, 344 can extend through a channel in the cutting head 375 proximal to the suture lock 376 and extend along the outside of the retaining catheter 373 and extend through the delivery catheter 100. The cutting head 375 can be coupled to the distal end of the cutting catheter 372. The retaining catheter 373 can extend through the interior lumen of the cutting catheter 372 so that the two catheters 372, 373 can be extended or retracted relative to each other.

[0096] Once the suture 74, 344 is locked (securely fixed) within the suture lock 376, the proximal end of the suture 74, 344 can be cut adjacent to the proximal side of the suture lock. The suture 74, 344 can be cut by advancing the cutting catheter 372 coupled to the cutting head 375 toward the proximal side of the suture lock 376. Figure 17 to Figure 18 Schematically illustrated, as the cutting head 375 advances along the holding catheter 373 toward the holding element 377, the cutting head brings the suture 74, 344 into close proximity with the cutting blade 379 positioned on the holding element 377. The cutting head 375 is configured to advance on the holding element 377 in such a way that the channel in the cutting head 375 that holds the suture 74, 344 becomes increasingly spatially occupied by the blade 379. When the blade 379 is forced into the channel of the cutting head 375, the blade 379 cuts the suture 74, 344. Applying proximal tension to the suture 74, 344 can facilitate the cutting of the suture 74, 344. In other embodiments, different actuations (e.g., rotation of the cutting catheter) can be configured to cut the suture 74, 344.

[0097] In some embodiments, more than two sutures may be employed, and these sutures may be locked within the suture lock 376 and severed in the same manner by the suture lock delivery subsystem 370. In some embodiments, advancement of the cutting head 375 over the retaining element 377 may facilitate the disengagement of the retaining catheter 373 from the suture lock 376. For example, the cutting head 375 may be advanced to a distal position where the cutting head 375 is configured to stabilize the suture lock 376 to allow the retaining catheter 373 to be axially and / or rotationally disengaged from the suture lock 376.

[0098] Fig.19A side view of an example of a suture lock 376 (shown with its outer shell / shell removed) is illustrated. The suture can be passed through the suture lock 376 from the distal end to the proximal end, as described elsewhere herein. The suture lock 376 may include a screw 382 that is configured to advance the push wedge 384 distally or retract it proximally, depending on the direction of rotation of the screw. The screw 382 may be rotated by a torque shaft 388. The torque shaft 388 may include a drive head that is configured to engage with a recess 381 (e.g., a polygonal recess or other non-circular recess, such as a proximal recess) positioned at the proximal end of the suture lock 376. Fig. 20 382) such that rotation of the torque shaft 388 causes rotation of the screw 382. The torque shaft 388 can extend through the interior lumen of the retaining catheter 373. The torque shaft 388 can be rotated at its proximal end by a knob 398 or other actuation mechanism positioned at the proximal end of the subsystem handle 396. The handle 396 can include a hemostatic valve 397. In some embodiments, the sutures 311, 344 can pass through the hemostatic valve 397.

[0099] The wedge 384 is pushed forward by the torque shaft 388 to gradually compress the ramp or angled surface 386 one or more springs, such as spring pins 388. The spring biases the clamp upward to open the suture path until it is forced to close by the rotation of the torque shaft 388. The compression of one or more spring pins 388 can force the clamp 390 to be downward on the suture 311, 344, thereby compressing the suture 311, 344 between two opposing surfaces. In some embodiments, the clamp 390 and the opposing surface 392 can have a notched surface configured to cooperate with each other in discrete increments. The notched surface of the cooperation can provide enhanced friction, and in some embodiments, provide mechanical interference, for keeping the suture 311, 344 between the opposing surfaces, so that they cannot be withdrawn from the suture lock 376 toward the proximal side or toward the distal side. In some embodiments, by rotating the torque shaft in the opposite direction, tightening can be reversible.

[0100] Once the suture lock is properly positioned over the suture 74, 344 and locked in place, the suture 74, 344 can be severed as described elsewhere herein. Fig.12 Retraction of the suture lock delivery subsystem 370 is depicted after the sutures 74, 344 have been cut. Once the suture lock delivery subsystem 370 has been removed from the delivery catheter 100, the delivery catheter 100 can be withdrawn from the body.

[0101] Although the disclosure describes certain embodiments and examples, many aspects of the above-mentioned systems and methods can be combined and / or modified in different ways to form yet other embodiments or acceptable examples. All such modifications and variations are intended to be included within the scope of the present disclosure. In fact, various designs and methods are possible and within the scope of the present disclosure.

[0102] In addition, certain features described in this disclosure in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment can also be implemented in multiple embodiments, either individually or in any suitable sub-combination. Moreover, although features may be described above as functioning in certain combinations, one or more features from a claimed combination can in some cases be excised from the combination, and the combination can be claimed as a sub-combination or a variation of the sub-combination.

[0103] Any particular feature, aspect, method, performance, characteristic, quality, attribute, element, etc. disclosed herein in conjunction with various embodiments can be used in all other embodiments described herein. Moreover, any method described herein can be practiced using any device suitable for performing the steps.

[0104] Moreover, although the components and operations can be depicted in the drawings or described in the specification in a specific arrangement or order, such components and operations do not need to be arranged and performed in the specific arrangement and order shown, nor do they need to be arranged and performed in the order of the sequence, nor do they need to include all components and operations to achieve the desired result. Other components and operations that are not depicted or described can be combined in the embodiments and examples. For example, one or more additional operations can be performed before, after, simultaneously or between any of the operations. Further, in other embodiments, operations can be rearranged or reordered. Moreover, the separation of the various system components in the above-mentioned embodiments should not be understood as requiring such separation in all embodiments, and it should be understood that the components and systems can generally be integrated together in a single product or packaged into multiple products.

[0105] In summary, various illustrative embodiments and examples are described herein. Although systems and methods have been disclosed in the context of these embodiments and examples, the disclosure extends beyond the specifically disclosed embodiments to other alternative embodiments and / or other uses of the embodiments, and to certain modifications and equivalents thereof. The disclosure expressly contemplates that the various features and aspects of the disclosed embodiments can be combined or substituted with one another. Therefore, the scope of the disclosure should not be limited by the specifically disclosed embodiments described above, but should only be determined by a reasonable reading of the appended claims and their full range of equivalents.

Claims

1. A novel tendon deployment system, comprising: a catheter having a proximal end and a distal end; a ventricular anchor subassembly extendable through the catheter, the ventricular anchor subassembly comprising: hub; a ventricular suture extending proximally from the hub; a ventricular anchor extending distally from the hub; a core wire extending through the ventricular anchor and beyond a distal end of the ventricular anchor; a flexible tubular sleeve extending proximally from the hub and having a length not exceeding 10 cm; a leaflet anchor deployment subassembly extendable through the catheter, having a radially expandable leaflet anchor within the leaflet anchor deployment subassembly and having a leaflet suture extending proximally through the catheter; and A suture locking subassembly is advanceable through the catheter and is configured to connect the ventricular suture to the leaflet suture, and the suture locking subassembly is constrained within the flexible tubular sleeve.

2. The new tendon deployment system according to claim 1, wherein: The radially expandable leaflet anchor includes wadding.

3. The new tendon deployment system according to claim 2, wherein: The wadding is transformable from an elongated strip configuration to a radially expanded, axially shortened configuration by proximal retraction of the leaflet sutures.

4. The novel tendon deployment system according to claim 1, wherein: The radially expandable leaflet anchor includes the leaflet suture positioned between two sheets of material.

5. The novel tendon deployment system according to claim 1, wherein: The radially expandable leaflet anchor is carried inside a needle having a pointed tip for piercing the leaflet.

6. The new tendon deployment system according to claim 5, wherein: The leaflet anchor deployment subassembly includes an elongated tube having a distal end and a central lumen, and a leaflet connector on the distal end of the elongated tube.

7. The new tendon deployment system according to claim 6, wherein: The leaflet connector includes a leaflet anchor.

8. The new tendon deployment system according to claim 7, wherein: The needle is axially movable relative to the leaflet anchor.

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